PRESCRIPTION PATTERNS IN MANAGEMENT OF HYPERTENSION AT KENYATTA NATIONAL HOSPITAL’S MEDICAL OUT PATIENT CLINIC.

Background to the study
Hypertension is an important public health challenge in both economically developing and developed countries. Significant numbers of individuals with hypertension are unaware of their condition and, among those with diagnosed hypertension, treatment is frequently inadequate. This global pandemic is of great public health concern because hypertension is the single most important cause of attributable mortality. It is a key contributory factor in the development of cardiovascular and cerebrovascular disease, and a major cause of stroke, myocardial infarction, heart failure and kidney disease.

Results from a large number of randomized clinical trials document conclusively that treatment of elevated systolic and/or diastolic blood pressure markedly reduces the risk of cardiovascular complications. Several internationally recognized guidelines for management of hypertension exist, each aimed at giving information obtained from the latest research to ensure proper management of patients. The purpose of this study therefore is to find out the extent these guidelines are adhered to in the management of high blood pressure at KNH’s out patient department.

Objectives of the study
1. To document the drugs commonly used in the treatment of hypertension.
2. To determine whether these drugs are rationally prescribed.
3. To compare management of hypertension at KNH with recommendations from international guidelines.

Methodology
The study was a retrospective description of 288 patients treated for hypertension at the medical out-patient clinic in KNH in the year 2007. The outpatient booking list for January to December 2007 was used to get file numbers for patients who attended the MOPC in 2007. The list of file numbers was used to retrieve a total of 2144 files. Sequential sampling was applied to obtain a total of 288 files for patients with hypertension fitting the inclusion criteria. Data from patient records were entered into data collection forms and keyed into a computer database using MS Access for analysis with SPSS 16.0.

Results
73.7% of patients were female and a majority were in the middle age and elderly populations. 55 % of patients were aged between 46-65 years, and 27% above 65 years. Most patients did not have any co morbidities, but hypertensive heart disease was leading among co morbidities affecting 20% of the patients. Various drug classes of antihypertensive drugs were used during the study period. Diuretics were the most frequently prescribed drugs accounting for 32.3% of all prescribed drugs not in combination. The next category was Beta blockers, 20.7% of all prescriptions, followed by CCB at 19.6% of prescribed drugs. Fixed Dose Combinations were 15.3 % of prescribed drugs. Prescription of the above drugs was rational in 78% of the 1140 hypertensive visits considered for the 288 patients from January to December 2007. Lower blood pressures were attained in those with mild hypertension at first presentation (mean pressure 138/87 mmHg) compared with moderate (144/90) and severe (149/93) mmHg.

Conclusion
In this study prescribing practice was consistent with local (MOH) and international guidelines (JNC and ESC/ESH) in choice of drugs, where the recommended diuretics and Beta blockers were prescribed at a much higher frequency than newer agents (ACEI and ARB’s). 79% of drugs were prescribed rationally for patients. 12% of the prescriptions were irrational on basis of factors related to BP of patients.

Recommendations
A study is needed on management of hypertensive patients with co-morbidities that constitute compelling indications for use of particular drug classes. Prospective studies on prescription patterns may help get over the hurdles limiting the retrospective study, including inconsistencies in the data recorded in patient treatment records.